Optical fiber connectors are specialized devices that must securely hold the terminal ends of optical fibers in very close coaxial alignment while maintaining an extremely small air gap between the polished ends of the fibers. Several standard connectors, or connector types, have evolved that perform that task to required specifications. Those connector types include, for example, an FC-type connector, an SC-type connector, an LC-type connector, an SCII-type connector and a biconic connector.
Over time, different optical fiber connector types have been adopted by different organizations, in different geographic areas and in different optical fiber networks. For example, FC-type connectors and STII-type connectors have been generally been adopted by AT&T corporation as its standard fiber optic connectors. As networks and organizations have been consolidated, however, situations are created where terminal facilities and other fiber optic cable facilities contain a mixture of different connector types. Further, technicians that are equipped to work on facilities containing one type of connector are frequently called upon to service facilities containing equipment based on a different type of connector.
Connector compatibility presents the greatest problems in situations where temporary connections between fibers must be made quickly. While in planned servicing and new installations special connector adapters can be made up ahead-of-time, that is not the case in emergency service restoration, such as in the case of a cable cut in the field. There have been many instances where service restoration was severely delayed because fiber jumpers that were on hand were incompatible with connectors that were in place in the network. Work in those cases had to be stopped until a special adapter was either made up or shipped in from another location.
Similar situations arise in field work where a fiber must be patched from one route to another, or where testing is performed using jumpers. A technician typically does not have in her possession an adapter for each and every connector combination that she may encounter on a typical job, and the job is frequently delayed because of that.
A modern permanent long-run fiber to fiber connection may require less than 0.1 dB power loss, and some applications even require less than 0.01 dB. That, however, is not the case in the testing and temporary patching that is frequently done on emergency fiber optic cable maintenance. In those cases, a 0.5 dB loss may be acceptable, at least for a temporary connection.
Attempts have been made to provide a universal fiber optic connector. In U.S. Pat. No. 6,224,270 to Nakajima et al., issued May 1, 2001, an adapter includes a ferrule that is spring-biased axially away from a snap-in plug. That portion of the adapter is installed on every fiber end. For each type of connector encountered, a special plug housing is provided that is compatible with the snap-in plug.
U.S. Pat. No. 6,508,593 to Farnsworth et al., issued Jan. 21, 2003, discloses a universal panel-mount system. In that system, a universal receptacle housing is mounted in an opening in the panel. A set of differently configured fiber optic adapters are specially designed to accept standard fiber optic connectors. Those adapters are configured to fit in the universal receptacle housing.
U.S. Pat. No. 5,333,221 to Briggs et al., issued Jul. 26, 1994, describes a universal fiber optic cable adapter that accepts diverse back panel assemblies that differ according to industry connector standards.
In each of those systems, it is necessary for a technician to have on hand a separate adapter for each connector type encountered. As noted, it is frequently the case that such an adapter is not at the site. Complications in procuring such an adapter are a major cause of delays in restoring telecommunications service after cable cut events.
Often, where temporary connections are made to restore service, fiber optic jumpers are used. In cases where cables with different connectors must be joined, the jumper itself may be the adapter having different connectors on the ends. Technicians often drape the jumper over a cabinet door, drape it over the equipment being used, or simply let it hang down from the bay. Such treatment could cause attenuations during testing or could damage the cable or the cabinet connection if the cable is dropped, bumped or snagged.
There is therefore presently a need for a method and apparatus for optically coupling fiber ends having disparate connectors, in a quick and efficient manner, without delay caused by procuring a special adapter. There is further a need for a device that safely positions the jumpers and cables being worked on during a restoration or other service. To the inventors' knowledge, there is no such apparatus or method currently employed to satisfactorily accomplish that task.